Method of and machine for piercing and eyeleting



April 13, 1937. s; L. 'GOOKIN ,5 6

METHOD OF AND MACHINE FOR PIERCING AND EYELETTING 1 Filed Dec. 24, 1954s Sheets-Sheet 1 3 Sheets-Sheet 2 S. L. GOOKIN METHOD OF AND MACHINE FORPIERCING AND EYELE TTING Filed Dec. 24, 1934 April 13, 1937.

April 13, 1937. 5. L. GOOKIN 2,076,556

METHOD OF AND MACHINE FOR PIERGING AND EYELET TING' Filed Dec. 24, 19545 Sheets-Sheet s I Fig. 5.

Patented Apr. 13, 1937 UNITED STATES PATENT OFFICE METHOD OF AND MACHINEFOR PIERCING AND EYELETING Application December 24, 1934, Serial No.758,886

27 Claims.

This invention relates to methods of and machines for piercing andeyeleting sheet material, and is herein disclosed with reference to aneyeleting machine having a pointed tool for piercing and dilating aneyelet-receiving hole in sheet-material, instead of a punch of the typethat cuts out a pill or disk to form a hole.

When eyelets or grommets are to be inserted and clenched in canvas suchas that used for sails and awnings, or even lighter fabrics such asthose .used for bath-curtains, it is usual not to cut out pills to formthe fastener-receiving holes, but to form the holes by puncturing thefabric with a pointed tool that is suitably tapered to spread the fabricwith or without severing some of the strands of the fabric. While thispractice is desirable to insure security of the fasteners in the fabric,the force required to thrust a pointed piercing tool through tightlywoven fabrics of the types mentioned is so great that the point of thetool has a strong tendency to develop wrinkles or puckers in the fabricby gathering too much of the latter adjacent to the fastener-receivinglocality. Finally, if an eyelet is inserted and clenched in fabric thuspuckered or otherwise distorted, it may, and in many cases does, gripthe malformations of the fabric so securely that they become permanent.

Although it has heretofore been proposed to provide eyelet-insertingmachines with means for clamping the eyelet-receiving material beforeand during the actual piercing thereof, the desirability of furnishingbacking for the material tangent to the piercing tool and of stretching5 or tensioning the material away from the tool have not heretofore beenrecognized.

With regard to these conditions, an object of the present invention isto provide improvements in methods of and means for piercing andeyeleting sheet material without removing any of the material andwithout gathering or puckering the material adjacent to the operatinglocality.

One aspect of the present invention consists in separating contiguousareas of a piece of sheet material to stretch or tension a narrowintermediate area, and piercing a hole in the latter area and insertingan eyelet into the hole while the tensioning force is maintained.

As herein illustrated the invention is embodied in a machineorganization comprising work-tensioning mechanism provided withcooperative tensioning members arranged initially to engage a surface ofthe fastener-receiving area of the work, means arranged to operateagainst those members to pierce a hole in that area and separate themembers laterally, and means arranged to insert a tubular fastener suchas an eyelet into the hole. I

Preferably, the work-tensioning means com prises at least two pairs ofclamping members arranged initially to clamp contiguous areas of thefastener-receiving material including the fastener-receiving area, eachpair being arranged to clamp one-half of the fastener-receiving area andto recede from the other pair as the hole is pierced between them,whereby the hole is enlarged'or spread by a stretching or tensioningforce to facilitate the entrance of the larger portions of the piercinginstrument and thereafter the entrance of a fastener. Moreover, theinitially contiguous edges of the clamping members remain in tangentrelation to the sides of the piercing instrument as it pierces anddilates the hole, thereby maintaining flatness of the material adjacentto the hole.

Various other features of the invention are hereinafter described andclaimed.

Referring to the drawings,

Fig. l is a front elevation of a fastener-inserting machine in which thepresent invention is embodied in a preferred form;

Fig. 2 is a front elevation of a toggle mechanism included in Fig. 1 butrepresented in its other extreme position;

Fig. 3 is a view on a larger scale, partly in section and partly inelevation, of the structure within the range of line IIIIII of Fig. 1,except that no portion of the raceway is included;

Fig. 4 is an elevation of the assembly in the upper part of Fig. 3 butviewed from the opposite side;

Fig. 5 is an elevation of the work-clamping members in the act ofclamping an interposed work-piece and about to impale it on the piercingelement; and a Fig. 6 is a similar view, partly in section and partly inelevation, at that point in the cycle of operations when the tools foroperating on the ,fastener are applying their final clenching pressure.

The general organization and many of the features of the illustratedmachine are as more fully shown and described in United States LettersPatent No. 2,007,274, granted July 9, 1935 on an application filed inthe name of J. A. Johnson. Briefly described, this machine comprises aframe In, a vertically movable fastener-inserting tool II, a stationarytool provided with a clenching shoulder l2, and a horn l3 rigidlysecured to the frame 10 to provide a support for the stationaryclenching tool. The tool II, which is of a well-known type commonly usedfor inserting grommets and eyelets, is provided with a centralspring-pressed spindle l4 and is carried toward and from the stationaryclenching tool by a slide l5 to which it is connected by a block 16. Theslide I5 is arranged in vertical guides 11 in the frame [B and isreciprocated by a wristpin 18 to which it is connected by a link 19. Thewrist-pin is carried by a rotary shaft 20 which also carries araceway-operating cam 2| and is driven by a one-revolution clutch (notshown),

the driving member of which is carried by a pulley 22 on which acontinuously driven belt may run. The clutch mechanism is of the typethat may be set in operation by depressing a treadle and is so organizedas to arrest the shaft when the wrist-pin I8 is at top center as 20shown in Fig. 1. Consequently, each operation of the clutch-controllingtreadle will cause the tool-slide l5 to execute one downward stroke andone upward stroke and to come to rest at its highest level.

As shown in Fig. 1 the machine also comprises a raceway 23 the deliveryend of which is arranged to present eyelets or grommets 24 to theinserting tool ll. Although the upper portion of the raceway is omittedfrom Fig. 1 because of lack of space it is to be understood that in itsentirety the raceway may be provided with a fastener-supplying hopper inaccordance with the disclosure in the aforesaid Johnson application.

For present purposes it will be sufiicient to point out that the racewayherein shown is mounted upon two horizontal studs 25 projecting from acarrier 26 and that the carrier is arranged to oscillate on a rod 21secured in bosses formed on the frame ID. A cam-roll 28 mounted on thecarrier 26 is maintained in contact with the cam 2! by a tension spring29 the lower end of which is attached to an anchoring pin projectingfrom the frame l0 and the upper end of which is attached to a pin 30affixed to the carrier. As usual in machines of this type the cam 2| isso designed as to cause the delivery end of the raceway to present afastener when the inserting tool II is in the upper stages of its rangeof travel, and to retract the delivery end during the down stroke of theinserting tool after the tip of the spindle 14 has been inserted intothe barrel of the eyelet or grommet presented thereto. The eyelet orgrommet is presented flange uppermost when taken by the spindle I4 (seeFig. 5).

Eyelets or grommets of the type herein shown are oblong rather thancircular, although it is to be understood that the invention hereinafterdescribed is not limited to fasteners of any particular shape The widedimension of the fastener is apparent in Fig. l and the narrow dimensionis apparent in Figs. 5 and 6. Accordingly, the spindle l4 has a widedimension apparent in Fig. 1 and a narrow dimension apparent in Figs. 3,4, 5 and 6. Referring particu- 5 larly to Fig. 3, the spindle isnormally projected from the inserting tool I by a spring 3|.

The lower tool by which the fasteners are to be clenched is providedwith an upstanding pilot 32 (Fig. 3) centrally located with respect tothe clenching shoulder I2. This pilot also has a wide dimension (seedotted lines in Fig. 1) and a narrow dimension apparent in Figs. 3, 5and 6, and its upper end is symmetrically beveled to form adouble-acting wedge having a piercing point and oppositely inclinededges converging thereto for the purpose of cutting a slit or gash inwoven fabric or other sheet material capable of being punctured thereby.To avoid dulling the point of the pilot 32, the lower end of the spindle[4 may be provided with a narrow kerf as clearly shown in Figs. 3, 5 and6, in the last of which the point is nested in the kerf. These figuresalso include an anchoring block 33 affixed to the horn l3 by bolts 34and providing a socket in which the stem or shank of the clenching toolis secured.

The anchoring block 33 also provides a mounting for a vertically movablework-supporting plate or table 35 from which four stems or guiderods 36project downwardly through corresponding bearing sleeves 3'! formed onthe block. The lower portions of the stems 36 are of smaller diameterthan the upper portions and are surrounded by compression springs 38that norm-ally sustain the plate or table 35 at its highest level whichmay be regulated by nuts 39 screwed on the lower ends of the stems. Thelower ends of the springs 38 are seated on shoulders at the lower endsof the bearing sleeves 31 but the upper ends of the springs are seatedagainst shoulders formed on the stems 36 at the portions where thelarger and the smaller diameters of the stems meet. When thework-supporting plate or table 35 is at its highest level as shown inFigs. 1, 3 and 5, its upper surface is slightly above the level of thepoint of the piercing element 32, and a work-piece may therefore beplaced thereon without any interference from the piercing element.

Two slidable work-clamping members 46, 40 are mortised into the uppersurface of the worksupporting plate 35 with oomplementaltongueand-groove formations as represented in Fig. l. Preferably theupper surfaces of the members 40 are slightly above the level of theplate 35 to restrict the clamping pressure of the fastener-receivingmaterial to the areas engaged by those members which are not onlymovable up and down with the plate 35 but are also movable edgewisetoward and from each other. Their movements away from each other areutilized to tension the fastener-receiving material. When the members 40stand in their initial positions as shown in Figs. 3 and 5 their inneredges abut each other in a vertical plane in register with the point andthe Work-slitting edges of the piercing element 32. To provide for thisrelation and to provide also for forcing the members 40 apart with awedging action, the contiguous ends 4| (Fig. 3) of these members areoppositely beveled in accordance with the tapering formation of thepiercing element 32. 7 Consequently, when the table 35 is depressed fromits highest level with pressure exerted upon a work-piece the clampingmembers 40 will be forced apart by the wedging effect of the piercingelement 32.

The clamping members 40 are moved toward and from each other bybell-crank levers 42 having trunnions 43 pivotally mounted in bearingscarried by the plate 35. One arm of each lever 42 projects upwardlythrough a slot 44 in the plate 35 and into a hole or socket formed inthe corresponding clamping member 49. The clamp-' ing members arenormally moved toward each other by torsion springs 45 of the safety-pintype, one arm of each spring being seated against the bottom of theplate 35 and the other arm being hooked into a hole formed in the otherarm of the lever 42. These levers are utilized also to impartsupplemental retractory movement to all the clamping members 40 afterthe latter have been separated as far as they may be by the piercingelement 32. The purpose of the supplemental retraction is to separatethe clamping members 40 enough to clear the clenching shoulder l2 of thelower tool when the work-supporting table is depressed to its lowestlevel as shown in Fig. 6. For this purpose the lower arms of the levers42 are arranged to be engaged by arresting abutments 46 which, as shown,are screwed into the anchoring block 33 and adapted to be adjustedvertically to regulate the extent of the supplemental retractorymovement in accordance with the lateral dimension of the clenchingshoulder l2. There is some lost motion between the levers 42 and thearresting abutments 46 when the work-supporting table is near itshighest level as shown in Figs. 1, 3 and 5, but while the table is inthe early stages of its downward movement the clamping members 40receive their initial separating movement from the wedging action ofthe, piercing element 32 as above described.

The work-supporting table also carries an edge-gage 4! (Figs. 1 and 5)adjustably secured thereto by a clamping bolt 48, the horizontal shankportion of the gage being provided with a slot 49 to receive the boltand to afford a range of adjustment.

One of the novel features of the present invention comprises twowork-clamping members 50, 50 arranged to cooperate respectively with theclamping members 40, 40. The members 50, 5B are arranged to bear uponcontiguous areas of the upper surface of the work and they are not onlymoved downwardly as hereinafter explained but they are also moved awayfrom each other while moving downwardly and while the clamping members48, are also moving downwardly and away from each other. When themembers 5!] are depressed against the work 5! as shown in Fig. 5 theyclamp initially that area of the work that is to be pierced and providedwith a fastener. Depression of. the work-supporting table 35 against thelifting force of the springs 38 is derived from the clamping membersthrough the medium of the interposed work-piece 5| (Figs. 5 and 6) ofwoven fabric or other sheet material capable of being pierced andprovided with fasteners. As shown in these figures the margin of thework-piece is folded to provide a two-ply hem in which the fastener orfasteners are to be inserted.

The work-clamping members 50 are carried by a. vertically movablecarrier 52 from which they are suspended by individual pivot pins 53,the work-engaging portions of these clamping members being formed toproject laterally under the delivery end of the raceway when the partsoccupy their initial positions as shown in Figs. 1 and 3. The axes ofthe pivot pins 53 are horizontal and are so situated that thework-engaging portions of the clamping members 50 may swing indirections virtually the same as those of the respective clampingmembers 48 with which they cooperate. 'I'he work-engaging portions ofthe clamping members 5!! are flat and are normally maintained inabutting edge-toedge relation by a compression spring 54 that surroundsa tie-rod 55. This rod extends through two pins 56 carried respectivelyby the clamping members and is provided with a head 51 at one end andwith one or more nuts 53 screwed on the other end. The head 5? is seatedagainst one of the pins 56 while the spring 54 is seated against theother and against one of the nuts 58. The abutting edges of the members50 lie in register with the point of the piercing element 32 and theyare slightly beveled or relieved to permit the point to enter betweenthem and force them apart with a wedging action without being dulled inconsequence. The wedging ac.- tion of the piercing element 32 issufficient to effect initial separation not only of the clamping members40 but also of the clamping members 5B, but after the latter have beenseparated in that manner they are separated further (see Fig. 6) toclear an ingoing fastener and the fastener-inserting tool H. Themechanism for effecting supplemental separation of the clamping members50 is hereinafter described.

The carrier 52 is.arranged to slide up and down in guides Ell, 60 formedin a detachable element 6| of the frame If], the element 6| beingutilized also to maintain the slide IS in its guides I7 and beingsecured in its operative position by attaching bolts 62. Verticalreciprocations are imparted to the carrier 52 by a toggle mechanism thatreceives its operating motion from the slide l5 and is organized todepress the clamping members to their lowest level when thefastener-inserting tool I4 is at an intermediate point in itsdownstroke. As shown in Figs. 1 and 2, the toggle mechanism comprises anupper link 63,.a lower link 64 and a pivot pin 65 connecting them andforming the knee-joint. The lower link 64 is connected to the carrier 52by a pivot-stud 66 while the upper link 83 is connected to the framemember 6| by a stationary anchoring pivot preferably designed to providea small factor of vertical adjustment. For the latter purpose the upperend of the link 63 is bored to receive a bushing having an hexagonalhead 61 adapted to receive a wrench by which it may be turned. Aneccentric hole bored through this bushing is occupied by a clamping bolt68 screwed into the member 6|. When the bolt 68 is set up tightly itclamps the bushing against the member 6| without applying any pressureto the toggle link 63, and the latter may therefore swing about thebushing without undue restraint, but when the bolt 58 is relaxed thebushing 61 may be turned to raise or lower the toggle mechanism and bothlimits of reciprocation of the carrier 52.

The operating movements of the tool-slide I5 are transmitted to thetoggle mechanism by a link 70, one end of which is connected to thetool-slide by a pivot-stud H and the other end to the link 63 by apivot-stud 72. The two extreme positions of the toggle mechanism areshown respectively in Figs. 1 and 2.

When the parts occupy their initial positions the clamping members 50are a considerable distance above the level of the work-supporting table35 as shown in Figs. land 3 to facilitate introduction and removal of awork-piece. As the toolslide l5 descends from its highest position itthrusts the spindle 14- through or into the barrel of the fastener 24then at the delivery end of the raceway, and at the same time operatesthe toggle mechanism by which the clamping members 50 are depressed. Atan early stage in the downward movement of the slide Hi, the deliveryend of the raceway is retractedv and the work-clamping members 50 engagethe work-piece as shown in Fig. 5 and thereby clamp it with considerablepressure against the lower clamping members 40.

No interruption occurs either in the downward movement of thefastener-inserting tool II or in the downward movement of thework-clamping members 50, but it is to be observed that the latter reachtheir lowest level when the knee 65 of the toggle mechanism reaches itsdead-center position, and that this point in the cycle is reached whenthe slide l5 has still a considerable distance to travel before reachingits lowest limit. As hereinbefore explained, both the lower clampingmembers and the upper clamping members are separated laterally by thewedging action of the piercing element 32 and it will, of course, beunderstood that this initial separation must result in tensioning thework because of the work-clamping pressure maintained by the springs 38in opposition to the depressing action of the clamping members 50.

The members 53 remain in contact with the sides of the piercing element32 until the hole in the fastener-receiving material has been completelypierced, to the end that the material adjacent to the hole shall not bepuckered or gathered as it would be if the members 50 were retractedfrom the piercing element before completion of the piercing operation.

Thereafter, the members 50 are retracted from i the sides of thepiercing element to stretch the work and to clear the ingoing fastener24 and the tool H. For this purpose, a supplemental wedge member 15 isaffixed to the tool-block l6, as shown in Fig. 1. The profile of thiswedge member is represented in dotted lines in Figs. 3, 4, 5 and 6.Referring to Fig. 5, the lower end of this wedge member is provided withoppositely inclined operating surfaces '56. Parallel vertical surfacesTl extend upwardly from the operating surfaces 16 to another pair ofoppositely inclined operating surfaces 18. The two series of surfacesthus provided are arranged to engage antifriction rolls 19, 19 mountedon studs 80 carried respectively by the clamping members 50.

The wedging surfaces 16 produce secondary separation of the members 53while the bell-crank levers 42 are causing secondary separation of themembers 40, and since the work is gripped tightly by both pairs of theclamping members at this stage these members stretch the worksufficiently to relieve its tightness on the piercing pilot 32.Moreover, their grip on the work is increased in consequence of theangular movement of the members 50 which now impress their inner edgesmore deeply into the upper surface of the work.

At a still later stage, the wedging surfaces 18 engage the rolls I9 andthereby cause a third and final stage of separation of the members 50(Fig. 6) to enable the tool H to pass between them without obstruction.When this final separation of the members 50 occurs a latch 8| carriedby one of the members 50 is automatically raised by a spring 82 (Fig. 4)until it reaches the positions shown in Fig. 6. The purpose of thislatch is to maintain separation of the members 53 until all the partshave returned to their initial positions. The latch BI is pivotallymounted on one of the pins 55 and its free end is arranged to engage acollar 83 surrounding the other pin 56 so that in performing itsfunction its effect is like that of a strut.

While the slide or carrier 52 is rising and is about to reach itshighest position, the latch Bl strikes an abutment 84 by which its freeend is disengaged from the collar 83 (see Fig. 4). The abutment 84 isthe lower extremity of a bar affixed to one of the bearings by clampingbolts 85 and is provided with slots 86 which provide for adjusting itvertically so that it may release the members 50 at the completion ofthe cycle of operations.

The parts of the machine stand initially in the positions shown in Figs.1, 3 and 4, the work-supporting table 35 being then slightly above thelevel of the point of the piercing pilot 32, and the clamping members 50being at or near their highest level. The fastener-inserting tool H isalso at or near its highest level and the delivery end of the raceway 23is in position to support a fastener in register with the spindle M.

The operator first places a work-piece 5| on the supporting table 35with the rear edge of the work against the gage 41. When the machine isset in operation, as by depressing a clutch-treadle (not shown), boththe slides l5 and 52 descend. When the spindle 14 has entered thefastener the raceway is retracted, and at about the same time themembers 50, having engaged the work as shown in Fig. 5, depress the workand the work-supporting table. As the work is being impaled upon thepiercing pilot 32 the two pairs of work-clamping members 40 and 50 arewedged apart laterally by the pilot and the work is thus tensioned andmaintained in a fiat condition.

After the two pairs of clamping members have been separated as far asthey may be by the wedging effect of the pilot 32 they are furtherseparated to stretch the material now impaled upon the pilot. Thesecondary separation of the members 40, 40 is caused by the bell-cranklevers 42 in consequence of their engagement with the abutments 4B andthe continued downward movement of the work-supporting table which, atthis stage, is relatively slow and decelerative because the knee of thetoggle is close to its dead-center position. The downward travel of thetool slide I5 is now relatively great, in consequence of which the wedgemember 15 causes the secondary stage of separation of the clampingmembers 50. At this stage the barrel of the fastener is thrust throughthe material 5| which is now under tension and being stretched. Afterthe barrel of the fastener has entered the material 5|, and while theknee-joint 65 of the toggle is at or near its dead-center position thewedging surfaces 18 of the member 15 engage the rolls I9 and therebycause a third stage of separation of the clamping members 50 to enablethe tool II to pass between them with out obstruction (see Fig. 6). Thetool ll now cooperates with the lower tool to upset and clench thefastener, the clamping members 50 being now locked in their openposition by the latching member 8|.

When the inserting tool ll rises to its initial position thework-supporting table 35 also rises under the influence of thecompression springs 38, thereby stripping the work from the pilot 32.During the final stage of the upward movement of the slide 52, thelatching member BI is dis engaged from the collar 83, and the clampingmembers 50 are thus released and permitted to close under the influenceof the spring 54. All the parts are now in their initial positions asshown in Figs. 1 and 3 and the operation of the machine is automaticallyarrested by the stopping mechanism.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. That improvement in methods of piercing and eyeleting sheet materialwhich consists in separating contiguous areas of the material latorallyand thereby tensioning a narrow intermediate area, piercing a hole insaid intermediate area, and inserting an eyelet into the hole while thetensioning force is maintained.

2. That improvement in methods of piercing and eyeleting sheet materialwhich consists in separating contiguous areas of the material laterallyand thereby stretching a narrow intermediatearea, piercing a hole insaid intermediate area while it is in process of being stretched, andinserting an eyelet into the hole before the intermediate area isrelieved from the stretching force.

3. That improvement in methods of piercing and eyeleting sheet materialwhich consists in separating contiguous areas of the material andthereby tensioningan intermediate area, piercing and dilating a hole inthe area so tensioned, bracing the rim of the hole against the piercingforce throughout the piercing and dilating period, and inserting aneyelet into the hole while the tensioning force is maintained.

4. That improvement in methods of piercing and eyeleting sheet materialwhich consists in 3 clamping contiguous areas of said material,separating said areas and thereby tensioning a narrow intermediate areaand at the same time piercing a hole in said intermediate area andtangent to said clamped areas, and inserting an eyelet' into the holewhile the tensioning force is maintained.

5. That improvement in methods of piercing and eyeleting sheet materialwhich consists in clamping two contiguous areas of the material, cuttinga slit in the material coincident with the common boundary line of theclamped areas, separating the clamped areas to spread the slit, andinserting an eyelet into the slit while the clamped areas are separated.

6. A fastener-inserting machine comprising work-tensioning mechanismprovided with cooperative tensioning members arranged initially toengage a surface of the fastener-receiving area of the work, meansarranged to operate against said members to pierce a hole in said areaand to separate said members, laterally, and means arranged to insert atubular fastener into said hole.

'7. A fastener-inserting machine comprising a tapered and pointedpiercing tool, work-tensioning mechanism provided with cooperativemembers arranged initially to clamp and movable to tension thefastener-receiving area of the work and impale it on said tool, andmeans arranged to insert a tubular fastener into the hole occupied bysaid tool.

8. A fastener-inserting machine comprising work-clamping mechanismhaving laterally separable pairs of clamping members arranged initiallyto clamp the fastener-receiving area of the work, a tapered and pointedtool arranged to pierce said area and separate said pairs of clampingmembers laterally, and means arranged to insert a tubular fastener intothe hole occupied by said tool.

9. A fastener-inserting machine comprising a movable fastener-insertingtool, a complemental tool having a shoulder for clenching the fastenerand having a tapering pilot for piercing the work, and work-tensioningmechanism arranged-to impale the work on said pilot and to engage thepilot while doing so.

10. A fastener-inserting machine comprising work-tensioning mechanismhaving two pairs of clamping members arranged initially to clamp afastener-receiving area of a work-piece, and fastener-insertingmechanism having a tapering work-piercing element arranged to engagecontiguous edges of said clamping members and thereby force said pairsof clamping members apart laterallywith a wedging action to tension thematerial in process of being pierced.

11. A fastener-inserting machine comprising mechanism arranged to moveadjacent portions of an article of sheet-material edgewise away fromeach other thereby tensioning an intermediate portion, an element ofsaid mechanism being a pointed tool arranged to pierce a hole in theportion so tensioned, and means arranged to insert a tubular fastenerinto the hole occupied by said tool.

12. A fastener-inserting machine comprising cooperative setting toolsone of Which is provided with a tapered pilot for piercing afastenerreceiving hole in a work-piece, mechanism for operating one ofsaid tools, and work-tensioning mechanism comprising separabletensioning members arranged initially to sustain one face of thefastener-receiving area of the work against distortion duringpenetration by said pilot and to be wedged apart by the latter, saidworktensioning mechanism also including means arranged to cooperate withsaid members to clamp the work.

13. A fastener-inserting machine comprising cooperativefastener-inserting tools one of which is provided with a tapered pilotfor piercing a hole to receive a fastener, mechanism for operating oneof said tools, and work-tensioning mechanism arranged to be operated intimed relation to said tool-operating mechanism, said work-tensioningmechanism having laterally separable work-clamping members arranged tobe wedged apart by said pilot as the latter pierces, the work.

14. A fastener-inserting machine comprising a tool-carrier, afastener-inserting tool carried thereby, a complemental setting toolarranged to cooperate with said fastener-inserting tool and having atapered pilot for piercing a hole in the work, toggle-mechanism operableby said toolcarrier, and Work-clamping mechanism arranged to be operatedby said toggle-mechanism to impale the work on said pilot, saidtoggle-mechanism being constructed and arranged to complete the impalingstroke of said work-clamping mechanism at an intermediate point in thefastener-inserting stroke of said tool-carrier.

15. A fastener-inserting machine comprising a tool-carrier, afastener-inserting tool carried thereby, a complemental tool providedwith a tapered pilot for piercing a hole in the work to receive afastener, and work-tensioning mechanism comprising yieldablework-supporting means and laterally separable members operable by saidtool-carrier to clamp the work against said means, said members beingarranged to be wedged apart by said pilot to tension the work as thepilot pierces it.

16. A fastener-inserting machine comprising downwardly yieldablework-supporting means, a tool provided with a fastener-clenchingshoulder below the work and with an upstanding tapering pilot forpiercing the work, downwardly movable work-depressing means comprisinglaterally movable members arranged to be wedged apart by said pilot,means arranged to separate said members further after their initialseparation by the pilot, and mechanism arranged to-insert a tubularfastener downwardly between said members and into the work on saidpilot.

1'7. A fastener-inserting machine comprising two pairs of work-clampingmembers each arranged initially to bear on that area of the work inwhich a fastener-receiving hole is to be pierced, fastener-insertingmechanism comprising relatively movable setting tools one of whichincludes a tapering pilot formed and arranged to pierce afastener-receiving hole in said area of the work and to force apart saidpairs of work-clamping members, and supplemental means by which saidpairs of members are forced further apart to clear said tools.

18. A fastener-inserting machine comprising depressible work-supportingmeans, a lower setting tool provided with an upstanding tapered pilotinitially below said means, mechanism arranged to clamp a work-pieceupon said means and depress both to impale the work on said pilot, saidmechanism having laterally separable work-clamping members arranged tobe wedged apart by said pilot to tension the work bein pierced, meansarranged to separate said members further after they have been wedgedapart by said pilot, and mechanism arranged to insert a fastener intothe hole formed and occupied by said pilot.

19. A fastener-inserting machine comprising a plurality of work-clampingcouples arranged to grip contiguous areas of a work-piece ofsheet-material, a tapering element arranged to force said couples apartlaterally and pierce an area of the work-piece from which they aredisplaced, supplemental means arranged to force said couples furtherapart, and means arranged to insert a fastener into the hole pierced bysaid tapering element.

20. In a fastener-inserting machine, in combination, a downwardlymovable fastener-inserting tool, a lower tool having a fastenerclenchingshoulder and a tapering work-piercing pilot projecting upwardlytherefrom, downwardly movable work-depressing means comprising laterallyyieldable members arranged to be wedged apart by said pilot as theyforce the work down on the pilot, and means arranged to effect furtherseparation of said yieldable members after the pilot has caused primaryseparation of them.

21. In a fastener-inserting machine, in combination, a lower tool havinga fastener-clenching shoulder and a work-piercing pilot projectingupwardly therefrom, a downwardly movable fastener-inserting tool,work-depressing means comprising laterally movable members arranged toforce the work down on said pilot, means arranged to separate saidmembers so that said fastener-inserting tool may pass between them,means arranged to maintain separation of said members while they arerising to their initial level, and means arranged to close said membersafter they have risen clear of the work.

22. In a fastener-inserting machine, in combination, a lower tool havinga fastenerclenching shoulder and a tapering work-piercing pilotprojecting upwardly therefrom, a downwardly movable fastener-insertingtool, downwardly yieldable work-supporting means comprising laterallymovable members arranged nor mally to support the work above said pilot,and downwardly movable means comprising laterally movable membersarranged to depress the work and said work-supporting members below thetop of the pilot, said work-supporting members and said work-depressingmembers being arranged to be wedged apart by said pilot as the latterpierces the work.

23. In a fastener-inserting machine, in combination, a lower tool havinga fastener-clenching shoulder and a tapering work-piercing pilotprojecting upwardly therefrom, a downwardly movable fastener-insertingtool, downwardly yieldable work-supporting means comprising laterallymovable members arranged normally to support the work above said pilot,downwardly movable means comprising laterally movable members arrangedto depress the work and said work-supporting members below the top ofthe pilot, said work-supporting members and said work-depressing membersbeing arranged to be wedged apart by said pilot as the latter piercesthe work, supplemental means arranged to separate said work-supportingmembers far enough to clear said fastener-clenching shoulder, andsupplemental means arranged to separate said work-depressing members farenough to clear said fastener-inserting tool.

24. A fastener-inserting machine comprising two cooperative settingtools arranged to operate against opposite ends of a tubular fastener,one of said tools being fixed and having a tapering pilot for piercing ahole in the work to receive the fastener, divided means arranged toengage the work initially in register with said pilot to impale the workthereon, mechanism arranged to cooperate with said divided means toclamp and tension the work, and mechanism for operating the other one ofsaid tools with movement toward and from said fixed tool.

25. A fastener-inserting machine comprising two cooperative toolsarranged to operate against opposite ends of a tubular fastener,mechanism for operating one of said tools with movement toward and fromthe other, one of said tools having a tapering pilot for piercing a holein the work to receive the fastener, divided means arranged to strip thework from said pilot, and divided means arranged to cooperate with saidstripping means to clamp the work while said pilot is piercing a holetherein, both of said divided means being arranged to be wedged apartlaterally by said pilot while the latter is piercin the hole.

26. A fastener-inserting machine comprising relatively movable toolsarranged to operate against opposite ends of a tubular fastener, one ofsaid tools having a tapering pilot for piercing a fastener-receivinghole in the work, worktensioning mechanism comprising clamping memberstwo of which are arranged initially to provide backing for that area ofthe work to be pierced and to be forced apart by entrance of said pilotbetween them, and supplemental means arranged to force said membersfurther apart to,

clear one of said tools.

27. A fastener-inserting machine comprising a

